Portolan Chart
F1. Maritime HistoryDefinition
Medieval Mediterranean coastal chart series of the thirteenth to sixteenth centuries.
The portolan chart is the medieval Mediterranean navigational chart that appeared in the late thirteenth century, drawn on vellum with a dense network of rhumb lines radiating from compass roses to lay off magnetic courses. Coastlines and ports were rendered with new accuracy for practical pilotage, the earliest surviving example being the Carte Pisane of about 1290. Catalan and Italian workshops produced richly decorated examples such as the 1375 Catalan Atlas. The charts mark the start of scientific European cartography.